On Wed, 1 Mar 2023 at 15:39, 'Alexander Potapenko' via kasan-dev <kasan-dev@xxxxxxxxxxxxxxxx> wrote: > > KMSAN must see as many memory accesses as possible to prevent false > positive reports. Fall back to versions of > memset16()/memset32()/memset64() implemented in lib/string.c instead of > those written in assembly. > > Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> > Cc: Daniel Vetter <daniel@xxxxxxxx> > Cc: Helge Deller <deller@xxxxxx> > Suggested-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> > Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx> Reviewed-by: Marco Elver <elver@xxxxxxxxxx> > --- > arch/x86/include/asm/string_64.h | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/x86/include/asm/string_64.h b/arch/x86/include/asm/string_64.h > index 9be401d971a99..e9c736f4686f5 100644 > --- a/arch/x86/include/asm/string_64.h > +++ b/arch/x86/include/asm/string_64.h > @@ -22,6 +22,11 @@ extern void *__memcpy(void *to, const void *from, size_t len); > void *memset(void *s, int c, size_t n); > void *__memset(void *s, int c, size_t n); > > +/* > + * KMSAN needs to instrument as much code as possible. Use C versions of > + * memsetXX() from lib/string.c under KMSAN. > + */ > +#if !defined(CONFIG_KMSAN) > #define __HAVE_ARCH_MEMSET16 > static inline void *memset16(uint16_t *s, uint16_t v, size_t n) > { > @@ -57,6 +62,7 @@ static inline void *memset64(uint64_t *s, uint64_t v, size_t n) > : "memory"); > return s; > } > +#endif > > #define __HAVE_ARCH_MEMMOVE > void *memmove(void *dest, const void *src, size_t count); > -- > 2.39.2.722.g9855ee24e9-goog > > -- > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20230301143933.2374658-3-glider%40google.com.